Levels, oral bioaccessibility and health risk of sand-bound potentially harmful elements (PHEs) in public playgrounds: Exploring magnetic properties as a pollution proxy

• Published in: Environmental pollution (1987) 2021-12, Vol.290, p.118122-118122, Article 118122
• Main Authors: Bourliva, A., Aidona, E., Papadopoulou, L., Ferreira da Silva, E., Patinha, C.
• Format: Article
• Language: English
• Subjects: Exposure assessment; Mineralogy; Oral bioaccessibility; Playground sand; Trace elements
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2021.118122

Children in urban environments are exposed to potential harmful elements (PHEs) through variable exposure media. Playing activities in outdoor playgrounds have been considered of high concern due to children's exposure to sand-bound PHEs through unintentional or intentional sand ingestion. Furthermore, the affinity of magnetic particles with dust-bound PHEs in playgrounds has been reported. In this study, playground sands (PG sands) from public playgrounds in the city of Thessaloniki, N. Greece were sampled and the levels, the contamination degree, oral bioaccessibility and exposure assessment of PHEs were evaluated. In addition, low-cost and fast magnetic measurements (i.e. mass specific magnetic susceptibility, χlf) were explored as potential pollution and health risk proxies. Mineralogically, siliceous PG sands dominated, while morphologically angular magnetic particles and Fe-rich “spherules” of anthropogenic origin were revealed and verified by enhanced χlf values. The average total elemental contents exhibited a descending order of Mn > Ba > Cr > Zn > Ni > Pb > Cu > Co > As > Sn > Bi > Cd, however only Cd, Bi, Pb, Cr, As and Zn were presented anthropogenically enhanced. Notable increase on PHEs levels and finer sand fractions were observed with continuous sand use. Anthropogenically derived elements (i.e. Cd and Pb with high Igeo values) exhibited higher bioaccessible fractions in PG sands and considered easily soluble in gastric fluids through ingestion. However, increased risks were found for specific PHEs (especially Pb) only in a worst case exposure scenario of an intentional sand ingestion (pica disorder). Statistical analysis results revealed a linkage of anthropogenic components with sand-bound magnetic particles. Moreover, the recorded high affinity of Pb contents (in an enhanced magnetized sub-set of PG sands) and bioaccessible Cd fractions with χlf provide a preliminary indication on the successful applicability of low-cost and fast magnetic measurements in high impacted playground environments. •Among studied elements Cd, Bi, Pb, Cr, As and Zn were anthropogenically enhanced.•Increase of PHEs levels was observed with continuous sand use.•Anthropogenic inputs were linked to sand-bound magnetic components.•Anthropogenically derived elements were more bioaccessible through ingestion.•Increased health risks were revealed only in a tested scenario of pica disorder.